This thesis reports on the development of a novel mass spectrometer combining image charge detection with surface induced dissociation for real-time analysis of intact viruses. Protonated viruses produced using electrospray are accelerated and subsequently impact on a solid surface. Capsid peptides released during the impact are analyzed using time-of-flight mass spectrometry. Image charge detection is used to measure the mass and charge states of structurally intact, electrosprayed viruses prior to impact. Since virus capsids are composed of loosely-bound proteins, collision of viruses with surfaces at moderate impact energies could release intact proteins. The masses and numbers of different protein types combined with the mass of the intact virus represent a unique signature useful for accurate, real-time virus identification. The progress of instrumentation developed thus far is reported. Techniques were developed for electrospraying intact viruses, including electrospray capillaries with small tips and methods for achieving complete desolvation. Significant reduction of low-frequency and other noise was achieved in the image charge detector as well as determination of accurate methods for mass and charge measurement. Improved focusing and transmission efficiency was achieved via an aerodynamic lens. Suitable surfaces were also obtained including conductive diamond and fluorinated self-assembled monolayer (SAM) surfaces.

We discuss the role of symmetries in the dissociative recombinations (DR) of three polyatomic ions, namely the linear HCO+ (formyl) ion and the two highly symmetric H+3 and H3O+ (hydronium) molecular ions. Regarding the HCO+ ion, we apply a quantum mechanical treatment using the Multi-channel Quantum Defect Theory (MQDT) formalism to describe the ion-electron scattering process. Our study takes into account the Renner-Teller effect in order to model the non Born-Oppenheimer vibronic coupling in linear polyatomic ions. The coupling has shown to represent the main mechanism responsible for electronic capturing in highly excited Rydberg states associated with excited vibrational levels of the ionic core. We consider all internal degrees of freedom of HCO+ and obtain the dissociative cross section as a function of the incident electron kinetic energy. We have also improved the theoretical approach by including the large permanent dipole moment of HCO+ using a generalization of the MQDT formalism. To our knowledge, this is the rst time the permanent dipole moment of an ion is included in a DR study. The obtained results are in good agreement with experimental data. We also study the DR of H+3 and H3O+ symmetric ions using a simpli ed theoretical treatment, which focuses on the key ingredient of the DR process, the electron capture in the rst excited degenerate vibrational normal mode of the ions through non Born-Oppenheimer Jahn-Teller coupling. For both ions the obtained cross sections are in very good agreement with the available experimental data. Moreover, in the case of H+3 , the results reproduce previous calculations from two independent theoretical studies. Finally, we investigate the role of symmetries in few body ultra-cold collisions by considering both three and four identical atoms systems. We derive allowed rearrangements of different fragments of the system, satisfying the complete symmetry of the molecular Hamiltonian. For that purpose we establish a correspondence between constants of motion of the system in di erent large-distance con gurations and irreducible representations of the total symmetry group. Selection rules (forbidden transitions) and allowed states, which depend on the fermionic or bosonic nature of the atoms, can be derived from these results.

Childhood maltreatment by a caregiver can occur in many forms, ranging from overt abuse to more subtle neglect. Amidst a primary focus on the outcome of posttraumatic stress disorder (PTSD), less research attention has been given to understanding the impact of maltreatment on one's developing sense of self, internal working model (IWM) of relationships, and emotion regulation capacities. Difficulties experiencing, regulating, and enjoying a full range of affect are common transdiagnostic features among adult survivors of child maltreatment, who frequently display emotional reactivity (e.g., mood swings, anger) and/or disengagement (e.g., numbing, dissociation). What makes the difference between individuals who lash out in emotional outbursts, those who tend to withdraw or dissociate, and those who frequently alternate between these two affective poles? In a mixed college and community sample of 417 adults, we explored two covert forms of childhood emotional maltreatment (e.g., chronic emotional disengagement and frightened/helpless parenting) as potentially linked to adult psychological and relational functioning. Controlling for the effects of childhood physical and sexual abuse, path analysis indicated that these types of maltreatment were significantly associated with insecure attachment patterns, emotional reactivity, and dissociation in adulthood. These findings inform therapeutic work with survivors of childhood trauma, signifying the importance of thorough assessment to uncover potential psychological legacies of emotional abuse and/or neglect, which can at times be overlooked or assumed to be less pathogenic than other more obvious forms of maltreatment.

This study quantitatively measures dissociation, rejection sensitivity, and identity distress among adults who experienced adoption as a child and the relationship between these factors. This study also compares groups of adoptees recruited through Amazon Mechanical Turk (MTurk) and social media to assess whether these two recruitment methods achieve similar results. An online survey was conducted of adopted adults and non-adopted adults to serve as controls using both MTurk and social media. A total of 539 participants were recruited representing 151 non-adopted individuals recruited exclusively through Mturk, and 388 adoptees, 247 of whom were recruited through MTurk and 141 through social media. Significant differences were found between adopted and non-adopted groups on the measures of dissociation, rejection sensitivity, and identity. Both rejection sensitivity and dissociation were also found to be significant mediating factors between adoption status and measures of identity. Significant differences were also found between adoptee recruitment methods on measures of dissociation, identity distress and rejection sensitivity with large effect sizes for dissociation and identity distress and a small effect size for rejection sensitivity. Implications for consideration in a clinical setting are discussed as well as potential areas of future research.

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No / The dissociation constant is one of the most important characteristics of a pharmaceutical chemical moiety which has to be estimated with accuracy. The development of in-situ speciation methods in solutions with parallel measurements using Raman spectroscopy (molecular) and pH (macroscopic) for the identification, characterization, and quantitative determination of citric acid species in aqueous solution by numerical data treatment using a multiwavelength curve fitting program over a range of pH values is described. As a result, the first, second and third stepwise dissociation constants of citric acid have been evaluated as 3.02±0.06, 4.78±0.06 and 6.02±0.04, respectively. From these data over the pH range 2.38-6.16 an excellent agreement with literature values was achieved.

Computational chemistry examination of the bond dissociation enthalpies of tungsten and main group elements. Includes quantification and calibration of theoretical methods to address the question of bond strengths including component σ and π molecular bonds.